Scott Group: Nanochemistry

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Scott Group Nanochemistry
Thorv 249
Jina
Mita
Mintang
Zahid
Nicole
Priya
robert.scott_at_usask.ca
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Scott Group Nanochemistry
Semiconducting CdSe Quantum Dots
4 nm 0.000004 mm
Colour changes with Size!
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Scott Group Nanochemistry
Solutions of Gold Nanoparticles also change
colour with Size!
Plasmon Band _at_ 520 nm

• Nanochemistry has old roots
• Colloidal Au used in Ancient Roman times
• Described by Faraday in 1857

Lycurgus Cup, 300 A.D. Bimetallic Au-Ag
nanoparticles http//www.thebritishmuseum.ac.uk
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Scott Group Nanochemistry
Metal Nanoparticles
Valden et al., Science 1998,281, 1647. Scott et
al., J. Phys. Chem. B 2005, 109, 692.
Chemistry changes with Size!
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Gold Nanoparticles
Mita Dasog

• Size control possible by adjusting ratio of
  HAuCl4 alkanethiol
• Monodispersity can be improved by fractional
  precipitation
• Brust et al., Chem. Commun., 1994, 801.

3.9 0.6 nm
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Gold Nanoparticles
Mita Dasog

• Size control possible by adjusting ratio of
  HAuCl4 alkanethiol
• Monodispersity can be improved by fractional
  precipitation
• Brust et al., Chem. Commun., 1994, 801.

3.9 0.6 nm
6.2 1.0 nm
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Gold Nanoparticles
Mita Dasog
Air oxidized
As synthesized

• Particle aggregation co-exists with
  alkanesulfonate formation
• Oxidation of thiols on Au surface by O2!

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Ionic Liquids for Materials Synthesis

• Liquids at Room Temp.
• No vapour pressure
• Low surface tension

Amine-stabilized Au Nanoparticles
Self-Assembly
Hydrolysis
TiCl4
TiO2
One pot synthesis of titania-Au catalysts!
Nicole Dehm Priyabrat Dash
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Continuing Work
Catalysis with Gold Nanoparticles in Solution
Tsunoyama et al., J. Am. Chem. Soc. 2005, 127,
9374.
Nicole Dehm
Barcode Nanowires for Chemical Sensing
Nicewarner-Pena, et al., Science 2001, 294,
137.
Mintang Liu
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Biophysicochemical Properties of Nanoparticles
(Bernie Kraatz, Matthew Paige)
How do nanoparticles interact with Lipid
membranes?
R NR3, SO4-, etc.
How does one detect single nanoparticle-biomolecu
le interactions?
How strongly nanoparticles associate with
biomolecules?
emission
Zahid Islam